Vehicle rear seat device

ABSTRACT

A vehicular rear seat unit ( 1 ) includes a bench seat ( 2 ) including a seat cushion ( 7 ) with three seat sections ( 4, 5, 6 ) arranged side by side, the seat cushion having a pair of frame members ( 23, 30, 24, 31 ) provided at positions corresponding to both side portions of the middle seat section ( 4 ); seat belt anchors (A, B, C, D) for the seat sections ( 4, 5, 6 ), the seat belt anchors (A, B, C, D) being attached to the respective frame members ( 23, 30, 24, 31 ); and a seat slide device ( 3 ) including a pair of movable rails ( 29 ) to which the respective frame members ( 23, 30, 24, 31 ) are individually fixed, and a pair of fixed rails ( 28 ) which slidably support the respective movable rails ( 29 ), the fixed rails ( 28 ) being individually fixed to a vehicle body floor.

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

The present Application claims the benefit of priority to the following international Applications: PCT Patent Application No. PCT/JP2003/005177 titled “Vehicular Rear Seat Unit” filed on Apr. 23, 2003 which published under PCT Article 21(2) on Nov. 6, 2003 as WO 03/091061 A1 in the Japanese language and Japanese Patent Application No. 2002-122906 filed on Apr. 24, 2002 (which are hereby incorporated herein by reference in their entirety).

FIELD

This invention relates to a vehicular rear seat unit in which a bench seat for three passengers is mounted on a seat slide device.

BACKGROUND

In a vehicular rear seat unit constructed by mounting a bench seat for three passengers, that is, a bench seat including a seat cushion having a middle seat section and right and left seat sections provided on both right and left sides of the middle seat section with the middle seat section sandwiched there between, on a seat slide device having two rails, the respective rails of the seat slide device are installed at positions corresponding to substantially transversely central parts of the right and left seat sections of the seat cushion, and a frame of the seat cushion is fixed to these rails.

The above-described rear seat unit has some problems. For example, the respective rails of the seat slide device are individually installed in the substantially transversely central parts of the one-side and the-other-side seat sections, and accordingly, impair cushioning characteristics of these seat sections, resulting in reduction of comfort of a vehicle.

Moreover, leg members fixing the respective rails of the seat slide device are located in the vicinity of doors, and hinder passengers from getting in and out of the vehicle, resulting in reduction of ease in getting in and out of the vehicle.

Furthermore, when an impact load is applied to a vehicle body due to a collision of the vehicle, and the like, a load of as much as 800 kg per one seat belt anchor of a passenger's seat belt is applied thereto, that is, a load of four to five tons in total is applied to the bench seat for three passengers with five to six seat belt anchors. In the above-described rear seat unit, points where the respective seat belt anchors are attached to the frame of the bench seat and points where the rails are fixed to the seat slide device are apart from one another. Accordingly, it is necessary to reinforce the bench seat for the impact load endurance, resulting in a complicated frame structure and in a weight increase of the rear seat unit.

SUMMARY OF THE INVENTION

The present invention is made in view of the above-described problems. An object of the present invention is to provide a vehicular rear seat unit including a seat belt attachment structure capable of surely restraining passengers, which realizes a simplified frame structure and weight reduction of a seat in addition to an improvement in comfort of a vehicle and ease in getting in and out of the vehicle.

In order to achieve the above-described object, an aspect of the present invention includes: a bench seat including a seat cushion with three seat sections arranged side by side, the seat cushion having a pair of frame members provided at positions corresponding to both side portions of the middle seat section; seat belt anchors for the seat sections, the seat belt anchors being attached to the respective frame members; and a seat slide device including a pair of movable rails to which the respective frame members are individually fixed, and a pair of fixed rails which slidably support the respective movable rails, the fixed rails being individually fixed to a vehicle body floor with leg members provided there between.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view of a frame structure of a vehicular rear seat unit according to an embodiment of the present invention, in which a cushion portion covering the frame structure is omitted.

FIG. 2 is a schematic view showing an arrangement of seat belts of the vehicular rear seat unit of FIG. 1.

FIG. 3 is an exploded perspective view of principal portions of the vehicular rear seat unit of FIG. 1.

FIG. 4 is a cross-sectional view showing an engaged state of catch brackets of the vehicular rear seat unit of FIG. 1.

FIG. 5 is a schematic view explaining loading directions when an impact load is applied to the vehicular rear seat unit of FIG. 1.

FIG. 6 is a partial, exploded view of principal portions of another embodiment of the catch brackets.

FIG. 7A is a partial cross-sectional view showing the catch bracket of FIG. 6 in a normal state.

FIG. 7B is a partial cross-sectional view showing the catch bracket of FIG. 6 in an engaged state when the impact loads are applied to the vehicular rear seat unit.

DETAILED DESCRIPTION

Referring generally to FIGS. 1-7, as best shown in FIG. 1, a rear seat unit 1 includes a bench seat 2, four seat belt anchors A, B, C and D, and a seat slide device 3.

The bench seat 2 includes a seat cushion 6 having a middle seat section 4, and a one-side (right-side) seat section 5 and the-other-side (left-side) seat section 7, which are provided on both right and left sides of the middle seat section 4 with the middle seat section 4 sandwiched there between, and includes a seat back 11 having a middle seat back section 8, and a one-side (right-side) seat back section 9 and the-other-side (left-side) seat back section 10, which are provided on both right and left sides of the middle seat back section 8 with the middle seat back section 8 sandwiched there between. A frame 17 of the seat back 11 is rotatably joined to a frame 16 of the seat cushion 7 with reclining devices 12 provided there between at a transversely central part of the bench seat 2 and with brackets 13 provided there between at both transversely outer side portions of the bench seat 2. Bar-like retaining or cross-frame members 14 and rod-like retaining or cross-frame members 15 are provided on the frame 16 of the seat cushion 7 and the frame 17 of the seat back 11, respectively.

As shown in FIG. 2, the seat belt anchors A, B, C and D are provided in two pairs on center frame members E and F of the seat cushion 7, which are provided at positions corresponding to the transversely outer side portions of the middle seat section 4. Specifically, the seat belt anchor A for the one side (right side) of the middle seat section 4 and the seat belt anchor B for the one-side seat section 5 are provided on one side (right side) and other side (left side) of the one center frame member E, respectively. On one side (right side) and other side (left side) of the other (left-side) center frame member F, the seat belt anchor C for the other-side seat section 6 and the seat belt anchor D for the other side (left side) of the middle seat section 4 are provided, respectively.

Here, the seat belt anchors A, B and C are buckles with which tongues (not shown) of a passenger b's seat belt 18, a passenger a's seat belt 19 and a passenger c's seat belt 20 are engaged, respectively. Moreover, the seat belt anchor D is an end to which one end 18 a of the seat belt 18 is fixed. The other end 18 b of the seat belt 18 is taken up by a retractor 22 fixed to an attachment 21 (refer to FIG. 1) of the-other-side seat back section 10 of the seat back 11. Ends 19 a and 20 a of the seatbelts 19 and 20, respectively, are individually fixed to both side sills (not shown) of a vehicle body. The other ends 19 b and 20 b of the seat belts 19 and 20, respectively, are individually taken up by retractors (not shown) fixed to both rear pillars (not shown) of the vehicle body.

Moreover, as shown in FIG. 3, the center frame members E and F of the bench seat 2 (in FIG. 2) are constituted by two base members 23 and 24, and box brackets 30 and 31 as bracket members for attaching these base members to movable rails 29.

The base member 23 has a substantially L-shape with an erected member 23 a and a lower member 23 b, and the base member 24 has a substantially L-shape with an erected member 24 and a lower member 24 b. Connecting brackets 25 and 26 are attached to the upper ends of the erected members 23 a and 24 a to be connected to the seat back 11, respectively, with reclining mechanisms (not shown) provided there between. The two reclining devices 12 have the erected members 23 a and 24 a, the reclining mechanisms, and the connecting brackets 25 and 26 (refer to FIG. 3). With regard to the erected members 23 a and 24 a, rear lower portions thereof are fixed by welding to a rear part of the frame 16 of the seat cushion 7. A front part of the frame 16 of the seat cushion 7 is fixed by welding to the movable rails 29, with brackets 44 provided there between (refer to FIG. 1).

As shown in FIG. 3, the box bracket 30 has an upper planer portion 30 a, and both sidewalls 30 b and 30 c extended downward from left and right ends of the planer portion 30 a, and has a channel-shape cross section. In a similar way, the box bracket 31 has an upper planer portion 31 a, and both sidewalls 31 b and 31 c extended downward from left and right ends of the planer portion 31 a, and has a channel-shape cross section.

The seat slide device 3 has two fixed rails 28 fixed to a vehicle body floor (not shown) with left and right leg members 27 provided there between, and the movable rails 29 which are slidably supported on the respective fixed rails 28 and have the base members 23 and 24 fixed thereto, respectively.

The base members 23 and 24 are fixed to the seat slide device 3 with the box brackets 30 and 31 interposed there between, respectively. Specifically, the lower member 23 b of the base member 23 and the lower member 24 b of the base member 24 are fixed by fixing screws 33 b to the sidewall 30 b of the box bracket 30 and the sidewall 31 b of the box bracket 31, respectively. Moreover, the planer portion 30 a of the box bracket 30 and the planer portion 31 a of the box bracket 31 are fixed to the movable rails 29 by fixing screws 33 a individually screwed to screw holes 32 provided in the movable rails 29. On the planer portions 30 a and 31 a, screw-housing concave portions which individually house heads of the fixing screws 33 a are formed.

In this embodiment, as shown in FIG. 3, the seat belt anchor A is fixed to the sidewall 30 c of the box bracket 30, the seal belt anchor B is fixed to the lower member 23 b of the base member 23, the seat belt anchor C is fixed to the lower member 24 b of the base member 24, and the seat belt anchor D is fixed to the sidewall 31 c of the box bracket 31. Note that, in FIG. 1 and FIG. 3, reference numerals 50 and 51 denote a lock lever and a lock release belt, respectively.

In the rear seat unit 1 configured in such a way, the bench seat 2 is fixed to the seat slide device 3 with the base members 23 and 24 interposed there between, which are provided at the positions corresponding to the both transversely outer side portions of the middle seat section 4 of the seat cushion 7. Accordingly, such structure members involved in fixing the bench seat 2 to the seat slide device 3 can be arranged away from central parts of the respective seat sections 4, 5 and 6. Therefore, good cushioning characteristics of the respective seat sections 4, 5 and 6 are maintained, and comfort of the vehicle is improved.

In addition, the seat slide device 3 can be installed close to the transverse center of the seat cushion 7. Accordingly, the leg members 27 can be arranged away from the vicinities of doors, and thus do not hinder passengers from getting in and out of the vehicle, whereby ease in getting in and out of the vehicle is improved.

Moreover, the seat belt anchors A and B are fixed to the base member 23, and the seat belt anchors C and D are fixed to the base member 24. Furthermore, both of the base members 23 and 24 are directly fixed to the movable rails 29 of the seat slide device 3. Accordingly, impact loads applied to the respective seat belt anchors A, B, C and D are directly transmitted to the vehicle body through the respective base members 23 and 24 and the seat slide device 3, which are highly rigid, without being transmitted through the frame 16 of the seat cushion 7 of the bench seat 2. Thus, an impact-resistant structure of the rear seat unit 1 is easily constructed, thus enabling simplification of the frame structure and weight reduction of the seat. Such transmission of the impact loads to the vehicle body is accurately performed in combination with high rigidities of the base members 23 and 24.

Moreover, in this embodiment, as shown in FIG. 3, on outer and inner edges of the respective leg members 27 in the transverse direction of the seat slide device 3, first catch brackets 34 and 35, each of which forms a groove open downward, are extended in parallel to the movable rails 29. The brackets 35 are formed longer than the brackets 34.

As shown in FIG. 4, from a lower edge of the lower member 23 b of the base member 23, which has the channel-shape cross section, a second catch bracket 36 is extended to be engaged with the first catch bracket 35 of the one (right-side) leg member 27 from a transversely inner side of the seat slide device 3. The second catch bracket 36 has an engagement piece 36 a formed by bending upward a transversely outer edge thereof. Moreover, in the vicinity of the second catch bracket 36, a protrusion 23 c is provided for attachment of the seat belt anchor B to the base member 23. To the outer sidewall 30 c of the box bracket 30, a second catch bracket 37 is fastened with a fixing bolt 38 together with the seat belt anchor A. The second catch bracket 37 is engaged with the first bracket 34 of the one leg member 27 from the transversely outer side of the seat slide device 3. The second catch bracket 37 has, in a lower end thereof, an engagement piece 37 a formed by bending upward and toward the transversely inner side.

In a similar way, as shown in FIG. 3, in a lower edge 24 b of the base member 24, which has the channel-shape cross section, a second catch bracket 39 is provided to be engaged with the first catch bracket 35 of the other (left-side) leg member 27 from the transversely inner side of the seat slide device 3. The second catch bracket 39 has, in a transversely outer edge thereof, an engagement piece 39 a formed by bending upward. Moreover, in the vicinity of the second catch bracket 39, a protrusion (not shown) for attachment of the seat belt anchor C to the base member 24 is provided. To the outer sidewall 31 c of the box bracket 31, a second catch bracket 40 is fastened with a fixing bolt 41 together with the seat belt anchor D. The second catch bracket 40 is engaged with the first catch bracket 34 of the other leg member 27 from the transversely outer side of the seat slide device 3. The second catch bracket 40 has, in a lower end thereof, an engagement piece 40 a formed by bending upward and toward the transversely inner side.

Specifically, in this embodiment, the respective second catch brackets 36, 37, 39 and 40 are provided close to the seat belt anchors B, A, C and D, respectively.

As shown in FIG. 3, a reinforcing rod 42 made of a rectangular cylindrical member is bridged between the left and right base members 23 and 24. To central parts of a rear side face of the reinforcing rod 42, two brackets 43 formed by bending into an L-shape are fixed by welding. The reinforcing rod 42 is fixed to tip ends of the base members 23 and 24 with the two brackets 43 provided there between. Specifically, the one (right-side) bracket 43 is put on a transversely outer side of the lower member 23 b of the base member 23, and is fixed to the sidewall 30 b of the box bracket 30 by the fixing screws 33 b. The other (left-side) bracket 43 is put on a transversely outer side of the lower member 24 b of the base member 24, and is fixed to the sidewall 31 b of the box bracket 31 by the fixing screws 33 b (refer to FIG. 1).

When an impact load is applied to the vehicle body from the front of the vehicle, as shown in FIG. 5, a forward impact load G1 due to inertia of the passengers sitting on the bench seat 2 is applied to the seat belts 18, 19 and 20, and reaction force G2 of the load G1 is exerted on the seat slide device 3 fixing the bench seat 2 to the vehicle body floor. At the same time, in order to cancel a moment caused by a difference in level between points of application of the load G1 and the reaction force G2, an upward load F1 is exerted on a rear side (seat back 11 side) of the seat cushion 7 of the bench seat 2 in a direction where the seat cushion 7 goes up, and a downward load F2 is exerted on a front side of the seat cushion 7 in a direction where the seat cushion 7 goes down.

For the upward load F1, the second catch brackets 36, 37, 39 and 40 are individually engaged with the first catch brackets 34 and 35, and thus the rear of the seat cushion 7 is prevented from moving upward. For the downward load F2, the reinforcing rod 42 comes into contact with upper surfaces of the movable rails 29, and thus the front of the seat cushion 7 is prevented from moving downward. Thus, the passengers are surely restrained.

Furthermore, in another embodiment of the first and second catch brackets, as shown in FIG. 6, a plurality of engagement holes 45 are arrayed on the tops of the first catch brackets 34 and 35 at [an] equal intervals along the length thereof, and on upper edges of the engagement pieces 39 a and 40 a of the second catch brackets 39 and 40, a plurality of engagement protrusions 46 are arrayed, at the same interval as that of the engagement holes 45, along the length thereof.

In a normal state, as shown in FIG. 7A, with regard to the second catch brackets 39 and 40, tip ends of the engagement protrusions 46 of the engagement pieces 39 a and 40 a thereof are apart from the first catch brackets 35 and 34. Accordingly, the second catch brackets 39 and 40 are movable relative to the first catch brackets 34 and 35. When an impact load is applied to the vehicle body and the upward load F1 (refer to FIG. 5) is exerted on the rear of the seat cushion 7, as shown in FIG. 7B, the second catch brackets 39 and 40 move upward, and the engagement protrusions 46 are engaged with the engagement holes 45. Thus, the second catch brackets 39 and 40 are prevented from moving relative to the first catch brackets 34 and 35. In a similar way, the other second catch brackets 36 and 37 are also prevented from moving relative to the first catch brackets; 34 and 35. Thus, the passengers are further surely restrained. 

1. A vehicular seat unit, comprising: a bench seat comprising a seat cushion with three seat sections arranged side by side, the seat cushion having a pair of frame members provided at positions corresponding to both side portions of a middle seat section; seat belt anchors for the seat sections, the seat belt anchors being attached to the respective frame members; and a seat slide device comprising a pair of movable rails to which the respective frame members are individually fixed; and a pair of fixed rails which slidably support the respective movable rails, the fixed rails being individually fixed to a vehicle body floor with leg members interposed there between.
 2. The vehicular seat unit according to claim 1, wherein: each of the leg members is provided on both transversely outer edges thereof with first catch brackets, each first catch bracket forming a groove open downward; each of the frame members is provided on both transversely outer edges thereof close to the seat belt anchors with second catch brackets, each second catch bracket having an engagement piece to be engaged with the first catch bracket; and a rod bridging each of the frame members there between, the rod for contact with the movable rails to prevent the seat cushion from moving downward.
 3. The vehicular seat unit according to claim 2, wherein: the first catch bracket is provided on a top portion thereof with a plurality of engagement holes arrayed along a length thereof; the second catch bracket is provided on a tip end of the engagement piece thereof with a plurality of engagement protrusions formed for engaging with the engagement holes; and the first and second catch brackets are configured such that the engagement protrusions are engaged with the engagement holes to prevent the second catch brackets from moving relative to the first catch brackets when an upward load is exerted on the seat cushion.
 4. The vehicular seat unit according to of claim 1, wherein the frame members each comprises base members, a reclining devices connected to a respective base member of the bench seat, and a respective bracket members for attaching each base members to a movable rails. 